Denke



(No Model.)

B. G. G. MOLDENKE.

ELEGTRO MAGNETIC AIR OOMPRBSSING BOOK DRILL.

INVENTOR.

ATTORNEYS.

UNITED STATES PATENT OFFICE.

RICHARD G. G. MOLDENKE, OF NEIV YORK, N. Y.

ELECTRO-MAGNETIC AIR-COMPRESSING ROCK-DRILL.

SPECIFICATION forming part of Letters Patent No. 394,203, dated December 11, 1888.

Application filed January 28, 1888. Serial No. 262,223. (No model.)

To ail whom, it may concern:

Be it known that I, RICHARD G. G. MOL- DENKE, a citizen of the United States, residing at New York, in the county and State of New York, have invented certain new and useful Improvements in Electro-Magnetic Air-Compressing Rock-Drills, of which the following is a specification, reference being had. to the drawings accompanying and forming a part of the same.

The object of this invention is the application of electro-magnetism to the operation of rock-drills and similar devices in a more practicable and efficient manner than has heretofore been done.

Previously to my invention rock-drills were operated by compressed air or steam con ducted from a compressor or boiler through pipes to the drill. The distance at which the drills may be practically and economically operated by this system is well known to be limited, while at even short distances the use of compressed air is attended with many obj e ctions due to the cooling which takes place by its expansion and other causes. Attempts have therefore been made to apply electromagnetism to operate the drills, the motors being run by currents conveyed perhaps a very long distance and with comparatively slight loss; but heretofore the great ditliculty has been in obtaining a practicable and eflicient combination of motorand drills. Reciprocating and rotary motors have both been employed; but they have always been directly connected to the drilling-tool. The fact that these devices have been used to only a very 5 limited extent would indicate that they have not fulfilled the requirements of practical working conditions, although they have been long known and improved in many ways. The main difficulty with these devices ap pears to result from the direct connection of the drill and motor, and by direct is meant either a pivotal connection with a crank or cranks on the motor-shaft direct or through an interposed spring. In seeking to avoid these objections I have produced a system which secures the advantages of both electromagnetic and mechanical pressure systems.

The invention, specifically stated, consists in combining with an electro-n'iagnetic motor one or more compression-cylinders provided with suitable valves and ports communicatin with a cylinder containing apiston to which the drilling-tool is connected, and beneath and above which the compressed air from the compression-cylinders is alternately admitted.

In other words, the essential feature of the invention is in the introduction into a drilling apparatus of an intermediate apparatus between the electric motor and the drill, by means of which air or equivalent fluid, after being broughtto a state of tension by the action of the motor, is caused to reciprocate the drill. Thus, in lieu of connecting the drilling-tool rigidly or directly to the movable element of the motor, I apply the power of the motor to the operation of the drill indirectly; but I thereby obtain a better and more practicable apparatus.

In carrying out my invention I may adopt many forms of drill, of motor, and of compressor, provided they be capable of such cooperative association as I have herein set forth. I have selected, however, a special form of mechanism, which is at the present time the best and most practicable known to me, in illustration of the principle of construction and mode of operation of the invention. This mechanism I shall now describe by reference to the accompanying drawings.

Figure 1 is a view in elevation of the complete apparatus. Fig. 2 is an enlarged sectional view of the compression and drilling cylinders on line .2? .r of Fig. 3. Fig. 3 is a horizontal section of Fig. 2, taken through the body of the cylinders. Fig. I is a detached perspective of a portion of the valve mechanism.

A is a solid plate or head secured to a lower plate, B, by bars C C, of which there are preferably two on opposite sides of the plates. These bars serve as guides, upon which the drilling apparatus is mounted so as to be capable of vertical adjustment.

D I) are the field-magnets of an electromagnetic motor of the Sprague or other similar type, provided with lugs d d, which surround the guide-bars and permit the motor to slide thereon.

The plates A B and guide-bars C constitute a frame, which is supported by the two Weighted legs E in front, pivoted to the plate B, and the long leg E in the rear, pivoted to the upper plate, A. The motor is moved along the guide-bars O and kept in proper adj ustment by means of a screw, A, swiveled to a non-magnetic block, a, bolted to the polepieces D.

F is a cylinder whose head is secured to the magnets D. The cylinder is adapted to move vertically through an opening in plate B, and being in fixed relation to the motor'it is-adjusted to the proper position by the screwA.

The cylinder F contains three compartments, or it may obviously be made up of three independent cylinders secured to or closed by the same heads. The compartments F F are the compression chambers or cylinders and the compartment F" is that in which the drillpiston works.

The part D of the motor is one of the un wound pole-pieces which surround the cylindrical or annular armature. To the ends of the armature-shaft, which is suitably mounted between the pole-pieces, are secured the cranks G G, which, by means of the connect ing-rods I I, are joined to the rods or pistons J J of the compression-cylinders F F, where by the rotary motion of the armature reciprocates the said pistons at a speed determined by the speed at which the motor is adjusted or regulated to run.

\Vithin the drill-cylinder F is a piston, H, to the rod of which the drilling-tool H is secured. Two ports or channels of communication between the drilling cylinder or compartment and each of the others are provided at or near the ends of the cylinders. These I have designated by letters I) c d 6. These ports are controlled by valves constructed to be automatically opened and closed by the movements of the pistonsas, for example, in the following manner: The valves P and B, respectively, are rigidly connected by rods f, extending through the compartments in the castings composing the cylinder F. The valves are blocks which are adapted to slide over the openings into the drilling-cylinder F, opening the lower ports when closing the upper ones, and conversely. Each valve is provided with tappets g, which are encountered by the pistons or by pins or other projections, 72, extending from them. Assuming, therefore, that the pistons J J are moving downward and the lower ports into the cylinder F are closed, the air in the lower ends of the cylinders is compressed until the tappets of the lower valves are struck by the projections on the pistons. This lets the compressed air under the piston H and raises it and the drill. On the upstroke of the pistons the air is compressed in the upper portion of the cylinders F F until the pistons raise the tappet-valves and let the air into the cylinder F above the piston H, which is thereby driven downward with great force. This operation is repeated at every stroke of the pistons.

As the rock is cut away the motor and compressor are lowered in the frame by means of the screw, and in other respects the management of the drill is similar to that of the ordinary air-drills. In the compression-cylinder heads I place small spring-valves L, through which air may enter the cylinders to supply leakage or air that passes the pistons. This type of air-compressor I prefer, as by using the same air over and over it avoids the necessity of artificially heating or cooling it.

The piston H or its rod or the tool attached thereto will in practice be provided with some suitable device for rotating it, and in other respects the usual accessories of these drills may be used and applied in well-understood ways.

I do not limit my invention, therefore, to the particular mechanism shown, nor to the peculiar conditions under which I have, for purposes of illustration, shown and described it herein as operating.

This drill presents many advantages over the ordinary air and steam drills now in use, for the reason mainly that the requisite energy or power for operating the drill is far more easily and economically conveyed to the drill from a distant source of power in the form of electricity than by compressed air,

steam, or otherwise.

\Vhat I now claim as my invention is 1. A drill-cylinder and piston, an air-compressor communicating with the drill-cylinder by valve-controlled ports or passages, and an electromagnetic motor adapted to operate the air-compressor, these parts being combined and mounted upon a portable supporting-frame, as herein set forth.

2. The combination, with a supportingframe, of an electro-magnetic motor, a reciprocating drill, an intermediate air-compressor for driving or reciprocating the drill and operated by the motor, and means for adjusting them in the frame, as set forth.

3. The combination, with a supportingframe, of a rotary electro-magnetic motor adjustably mounted in guides on said frame, air-compressing cylinders and pistons secured to said motor, an air-drill operated by the compressor, and connections between the motor and air-compressor for reciprocating the pistons of the same, as set forth.

4. The combination, with a supportingframe, of a rotary electro-magnetic motor, aircompressing cylinders with reciprocating pistons operated by the motor, a drill-cylinder having passages of communication with the compressor-cylinders on opposite sides of the pistons therein, and automatic valves With tappets in the paths of movement of the compressor-pistons controlling said passages, as set forth.

RICHARD G. G. MOLDENKE.

Vitnesses:

RoBr. F. GAYLORD, ERNEST HOPKINSON. 

